Successful treatment of corneal hypertrophic scar in Hurler syndrome

Key Clinical Message In Hurler syndrome, corneal opacification is a common finding but rarely manifests as hypertrophic scars. A 6‐year‐old boy with Hurler syndrome had a hypertrophic scar on his left eye, which was successfully treated with superficial keratectomy.

A 6-year-old Iranian boy, confirmed to have MPS type I using a genetic study and with a positive family history of MPS I in his brother, was referred to our out-patient clinic of ocular diseases of referral eye hospital of Isfahan University of Medical Sciences, Iran.The patient had been complaining about visual disturbance for the past 2 days.The patient had no history of any ocular trauma, mechanical or medical intervention and any ocular manipulation.
Extraocular manifestations of the patient were as follows: developmental delay, short stature, thoraco-lumbar kyphosis, facial coarsening, enlarged lips, cardiomyopathy, and sensorineural hearing loss.

INVESTIGATIONS, AND TREATMENT
On slit lam examination there was a mild corneal clouding in both sides and a hypertrophic scar on the central cornea of left eye (Figure 1).Dilated funduscopic examination was unremarkable.Diagnoses was established up by clinical examination and then confirmed using ophthalmic optical coherence tomography (OCT) (Figure 2).
Patient underwent SK and the postoperative course was uneventful without any further complications.After intravenous sedation, operated eye was anesthetized using Tetracaine ophthalmic drops (Anestocaine, Sina Darou Laboratories, Tehran, Iran).Corneal epithelium was removed following the instillation of alcohol drops (20% alcohol for 15 s).Hypertrophic and fibrous tissues were scraped using a #64 beaver blade.Mitomycin-C (MMC 0.02%) soaked sponge was placed over the area of debrided cornea for 90 s.The cornea was irrigated with normal saline solution and a bandage contact lens (Aquvue Oasys) was placed on the eye.Postoperative medications regimen included the application of topical levofloxacin (Sina Darou, Tehran, Iran) and Betamethasone (Sina Darou, Tehran, Iran), both of which were administered four times a day for a duration of 1 month.

| OUTCOME AND FOLLOW-UP
No signs of inflammation were observed.After the operation, measured corneal thickness was within the normal range.Also, the patient was satisfied with their visual acuity and ability in 4 weeks follow-up visit (Figure 3).During 12-months of follow-up, no evidence of recurrence was observed.

| DISCUSSION
According to the global MPS I registry outcomes, 9 70.9% of Hurler cases will manifest corneal clouding at the median age of 1.1 years.][12][13] Nodular lesions on the cornea are a rare occurrence and can have various etiologies. 14Corneal hypertrophic lesions, such as keloids, have been documented in several congenital syndromes and ophthalmic anomalies (e.g., Lowe's syndrome and Rubinstein-Taybi syndrome); however, primary keloid lesions are seldom reported. 15As far as we are aware, this is the first reported case of a patient with Hurler syndrome and corneal nodular lesion in the literature.
SK was introduced in 1952 16 and has been utilized to treat ocular surface disorders.In this simple procedure the corneal epithelium is debrided whilst the Bowman's layer is preserved. 17Typically, the manual dissection of superficial corneal layers is performed using a surgical blade or sterile sponge. 18The use of MMC, as an antimetabolite with the goal of diminishing the activity of keratocytes and fibroblasts, is recommended to prevent the recurrence of the lesion and decrease the likelihood of corneal haze following SK. 18SK is a very effective treatment method for corneal nodules and has is demonstrated to have remarkable efficacy in terms of recurrence prevention.However, it has some limitations such risk of postoperative corneal haze. 18 conclusion, we described the coincidence of a nodular hypertrophic corneal lesion and corneal clouding in a 6-year-old patient with Hurler syndrome, highlighting a rare but possible manifestation of this disease.Furthermore, we have presented SK as a successful treatment method of the specified lesion.

F I G U R E 1
Mild corneal clouding with a hypertrophic scar on the left cornea.F I G U R E 2 Hyperreflective lesion on anterior optical coherence tomography compatible with hypertrophic scar on the left central cornea.